Keep AudioScheduledSourceNode alive until onended is called.

Source/modules/webaudio/AudioScheduledSourceNode.cpp

 /*
  * Copyright (C) 2012, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 24 matching lines @@
 #include "wtf/MathExtras.h"
 
 using namespace std;
 
 namespace WebCore {
 
 const double AudioScheduledSourceNode::UnknownTime = -1;
 
 AudioScheduledSourceNode::AudioScheduledSourceNode(AudioContext* context, float sampleRate)
     : AudioSourceNode(context, sampleRate)
+    , ActiveDOMObject(context->scriptExecutionContext())
     , m_playbackState(UNSCHEDULED_STATE)
     , m_startTime(0)
     , m_endTime(UnknownTime)
     , m_hasEndedListener(false)
+    , m_notifyingEndedListener(false)
 {
 }
 
 void AudioScheduledSourceNode::updateSchedulingInfo(size_t quantumFrameSize,
                                                     AudioBus* outputBus,
                                                     size_t& quantumFrameOffset,
                                                     size_t& nonSilentFramesToProcess)
 {
     ASSERT(outputBus);
     if (!outputBus)
@@ skipping 78 matching lines @@
 void AudioScheduledSourceNode::start(double when)
 {
     ASSERT(isMainThread());
     if (m_playbackState != UNSCHEDULED_STATE)
         return;
 
     m_startTime = when;
     m_playbackState = SCHEDULED_STATE;
 }
 
-void AudioScheduledSourceNode::stop(double when)
+void AudioScheduledSourceNode::stopNote(double when)
 {
     ASSERT(isMainThread());
     if (!(m_playbackState == SCHEDULED_STATE || m_playbackState == PLAYING_STATE))
         return;
 
     when = max(0.0, when);
     m_endTime = when;
 }
 
 void AudioScheduledSourceNode::noteOn(double when)
 {
     start(when);
 }
 
 void AudioScheduledSourceNode::noteOff(double when)
 {
-    stop(when);
+    stopNote(when);
 }
 
 void AudioScheduledSourceNode::setOnended(PassRefPtr<EventListener> listener, DOMWrapperWorld* isolatedWorld)
 {
     m_hasEndedListener = listener;
     setAttributeEventListener(eventNames().endedEvent, listener, isolatedWorld);
 }
 
 void AudioScheduledSourceNode::finish()
 {
     if (m_playbackState != FINISHED_STATE) {
         // Let the context dereference this AudioNode.
         context()->notifyNodeFinishedProcessing(this);
         m_playbackState = FINISHED_STATE;
         context()->decrementActiveSourceCount();
     }
 
     if (m_hasEndedListener) {
-        // Reference ourself so we don't accidentally get deleted before notifyEnded gets called.
-        ref();
+        m_notifyingEndedListener = true;
+        setPendingActivity(this);
         callOnMainThread(&AudioScheduledSourceNode::notifyEndedDispatch, this);
     }
 }
 
 void AudioScheduledSourceNode::notifyEndedDispatch(void* userData)
 {
     static_cast<AudioScheduledSourceNode*>(userData)->notifyEnded();
 }
 
 void AudioScheduledSourceNode::notifyEnded()
 {
     // Avoid firing the event if the document has already gone away.
     if (context()->scriptExecutionContext()) {
         RefPtr<Event> event = Event::create(eventNames().endedEvent);
         event->setTarget(this);
         dispatchEvent(event.get());
     }
+    m_notifyingEndedListener = false;
+    unsetPendingActivity(this);
+}
 
-    // Deref to match the ref() call in finish();
-    deref();
+ScriptExecutionContext* AudioScheduledSourceNode::scriptExecutionContext() const
+{
+    return context()->scriptExecutionContext();
+}
+
+void AudioScheduledSourceNode::stop()
+{
+    if (m_notifyingEndedListener)

[haraken, 2013/09/09 17:58:51]

How about just using hasPendingActivity() instead of introducing
m_notifyingEndedListener?

[Raymond Toy (Google), 2013/09/09 18:23:45]

Done. m_notifyingEndedListener removed.

+        unsetPendingActivity(this);
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)